Method and apparatus for bleaching furniture

ABSTRACT

A method and apparatus is utilized for bleaching furniture through the use of hydrogen peroxide and ammonia. The furniture to be bleached is placed on a conveyor which passes through an air lock structure into an ammonia chamber. Ammonia is delivered to the ammonia chamber and causes the bleaching of the furniture. The bleached furniture component is removed from the ammonia chamber through an air lock structure.

United States Patent Baymiller Nov. 25, 1975 METHOD AND APPARATUS FOR 1,186,604 6/1916 Petersen-Hviid 117/57 BLEACHING FURNITURE 1,680,529 8/1928 Richter et a1 117/57 3,645,666 2/1972 Bailey 117/57 [75] Inventor: John W. Baymiller, Lancaster, Pa.

[73] Assignee: Armstrong Cork Company, I

Lancaster, p Primary Examiner-Michael R. L'usignan [22] Filed: Mar. 4, 1974 [21] Appl. No.: 447,894

Related US. Application Data Continuation of Ser. No. 253,172, May 15, 1972, abandoned, which is a division of Ser. No. 101,487, Dec. 28, 1970, Pat. No. 3,708,889.

US. Cl. 427/254; 427/345; 427/351;

/11 1 1m. 01. D06L 3/02 Field of Search 427/254, 345, 351; 8/111 References Cited UNITED STATES PATENTS 7/1906 Lutter 117/108 [57] ABSTRACT A method and apparatus is utilized for bleaching furniture through the use of hydrogen peroxide and ammonia. The furniture to be bleached is placed on a conveyor which passes through an air lock structure into an ammonia chamber. Ammonia is delivered to the ammonia chamber and causes the bleaching of the furniture. The bleached furniture component is removed from the ammonia chamber through an air lock structure.

2 Claims, 1 Drawing Figure D t3\i 9 Q2:

US. Patent Nov.25,1975 3,922,397

METHOD AND APPARATUS FOR BLEACHING FURNITURE N This is a continuation of application Ser. No.

253,172, filed May 15, 1972, now abandoned, which is a division of application Ser. No. 101,487, filed Dec. 28, 1970, now U.S. Pat. No. 3,708,889.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention is directed to a bleaching method and apparatus and, more particularly, to a method and apparatus for bleaching furniture by means of hot ammonia gas acting as a catalyst on the hydrogen peroxide.

2. Description of the Prior Art Ammonia has been used in the past as a bleaching catalyst. However, it is not normal practice in the furniture industry to use ammonia for bleaching due to the inherent hazards in the use of ammonia.

The use of air locks for the purpose of transmitting an item from one area to another so as to isolate the two areas is a feature which is old in a number of arts.

However, the prior art lacks the specific teaching of the novel combination of elements whichnow permit the utilization of ammonia for bleaching of furniture components.

SUMMARY OF THE INVENTION The invention herein is a method and apparatus for the hydrogen peroxide and ammonia treatment of wood components for furniture to bleach the same. A conveyer structure moves in a circular pathway from outside of the ammonia treating unit to the inside of the ammonia treating unit. Furniture components are loaded on a carrier carried by the conveyer structure. The carrier and furniture component passes through one vapor-tight door structure into a vapor-tight chamber which is an air lock. The carrier and funiture component then passes into the ammonia chamber where ammonia will cause the bleaching of the furniture,

which has been coated with hydrogen peroxide. The ammonia may be placed in the ammonia chamber in the form of aqueous ammonia or vaporized dry ammonia gas. After the prescribed time for bleaching has occurred, the furniture component then passes out of the ammonia chamber into a second air lock, and from the second air lock back to the original starting position where the bleached component is removed from the carrier and a new component is placed on the carrier for bleaching.

BRIEF DESCRIPTION OF THE DRAWING The drawing is a schematic view of the apparatus for carrying out the invention herein.

DESCRIPTION OF THE PREFERRED EMBODIMENT The bleaching apparatus comprises an oval conveyer structure 2 which is used to transport the furniture component through the bleaching apparatus. A carrier structure 4 is mounted on the conveyer structure, and this carrier will carry the furniture component 6 which is to be bleached by the hydrogen peroxide and ammonia. The conveyer structure is intermittent in operation and may be any conventional type of intermittent conveyer structure. A furniture component is loaded onto the conveyer at position A. Operation of the conveyer carries the carrier 4 and furniture component 6 into the 2 airlock B. The air lock B has an entrance door 8 and an exit door 10. The doors are conventional vapor-tight door structures and open on a prescribed sequence of operation. When the door 10 is closed, door 8 will open and permit the carrier and furniture component to move into the air lock B. Due to the presence of some residual ammonia gas in air lock B, an exhaust system 12 is located adjacent door 8 so that the opening of door 8 does not necessarily mean that ammonia gas can escape out into the area A. The exhaust system 12 tendsto pull the ammonia gas from the vicinity of the door 8 'so that there is actually a flow of air from area A to B rather than from area B to A. Once the carrier and furniture component are within air lock B, the door 8 is closed.

Only after door 8 is closed "can door 10 open. Door 10 is opened and the carrier and funiture component may now move into the ammonia bleaching chamber C. Once the carrier and furniture component are within the chamber C, the door 10 will close. It is through the opening of door 10 that some ammonia gas can move into ara B, and that is why the exhaust system 12 must be utilized to prevent this ammonia from escaping out into'area A. The furniture component stays in the ammonia treating area C the required period of time.

When this period is done, door 14 opens, and the carrier and bleached furniture component may now move into air lock D. When door 14 is opened, door 16 is closed. Once the carrier and furniture component are in air lock D, door 14 will close. In the meanwhile, another carrier and furniture component has entered the ammonia chamber C from air lock B. With the door 14 closed, door 16 can now be opened to permit the carrier and bleached furniture component to move back out to area A. At this point, the carrier will be offloaded and a new unbleached furniture component placed thereupon. An exhaust system 18 is used in a manner like exhaust system 12 to prevent escape of ammonia gas from air lock D into area A.

The door structures 8, l0, l4 and 16 are vapor-tight and are similar to those set forth in U.S. Pat. No. 3,363,324 or any other like type structures. Particular success has been secured with corrugated metal doors which operate like conventional garage doors. The conveyer structure is a simple intermittent conveyer structure which need only have a flat surface upon which furniture components may be positioned for movement into the ammonia chamber C. The door structures are coordinated in their operation so that areas B and D may function as air locks.

The ammonia being supplied to the ammonia bleaching area C may be in the form of dry gaseous ammonia. The ammonia is supplied in liquid form and is passed through a vaporizer which is nothing more than a steam-heated jacketed tube. The liquid ammonia is converted to a gas, and the gas is fed through appropriate pressure reducing and control structures so that the required amount of dry gaseous ammonia is supplied to the chamber C by passageway 22. When dry gaseous ammonia is utilized, the chamber is heated to l-200 F. by a separate heat source and the ammonia concentration is 35%.

It is also possible to use aqueous ammonia. Aqueous ammonia is stored without pressure. It is pumped to a spray distributor structure 20 where the ammonia in liquid form is sprayed out into the passageway 22. Incoming heated air passes along the passageway 22 by the distributing head 20 and propels the atomized amthe chamber is maintained at l80200 F., and the ammonia concentration is 35 The furniture component is kept inthe chamber C for 3 to 5 minutes when dry gaseous ammonia is utilized and for 3 to 5 minutes when aqueous ammonia is utilized under the above conditions.

What is claimed is:

l. The method of bleaching furniture components in a treatment apparatus comprising the steps of:

a. moving a plurality of. furniture components on an intermittently operated conveyor 7 structure to move the furniture components in an endless path,

b. opening an entrance door to a first air lock means and moving a first furniture component into said first air lock,

0. closing said entrance door to said first air lock means and then opening an exit door of said first air lock means, said exit door connecting said first air lock means with furniture component treatment area,

d. moving said first furniture component from said first air lock to said treatment area, and then closing said first air lock means exit door,

e. moving a second furniture component into said first air lock means,

f. spraying aqueous ammonia into said treatment area and bleaching said first furniture component with the ammonia for the required period of time,

g. opening an entrance door to a seond air lock means, said last mentioned entrance door connecting said treatment area with said second air lock means,

h. moving said first furniture component into said second air lock means, and closing the entrance door of said second air lock means while at the same time moving said second furniture component into said treatment area,

'. then opening an exit door of said second air lock means and moving said first furniture component from said second air lock means to the point wherein the first furniture component started its movement towards the first air lock means.

2. The method of claim 1 wherein there is the further step of:

exhausting air from the vicinity of the entrance door of the first air lock means and the exit door of the second air lock means to prevent residual ammonia gases in said air lock means from escaping from within the treatment apparatus to the area outside of the treatment apparatus. 

1. THE METHOD OF BLEACHING FURNITURE COMPONENTS IN A TREATMENT APPARATUS COMPRISING THE STEPS OF: A. MOVING A PLURALITY OF FURNITURE COMPONENTS ON AN INTERMITTENTLY OPERATED CONVEYOR STRUCTURE TO MOVE THE FURNITURE COMPONENTS IN AN ENDLESS PATH, B. OPENING AN ENTRANCE DOOR TO A FIRST AIR LOCK MEANS MOVING A FIRST FURNITURE COMPONENT INTO SAID FIRST AIR LOCK, C. CLOSING SAID ENTRANCE DOOR TO SAID FIRST AIR LOCK MENAS AND THEN OPENING AN EXIT DOOR OF SAID FIRST AIR LOCK MEANS, SAID EXIT DOOR CONNECTING SAID FIRST AIR LOCK MEANS WITH FURNITURE COMPONENT TREATMENT AREA, D. MOVING SAID FIRST FURNITURE COMPONENT FROM SAID FIRST AIR TO SAID TREATMENT AREA, AND THEN CLOSING SAID FIRST AIR LOCK MEANS EXIT DOOR, E. MOVING A SECOND FURNITURE COMPONENT INTO SAID FIRST LOCK MEANS, F. SPRAYING AQUEOUS AMMONIA INTO SAID TREATMENT AREA AND BLEACHING SAID FIRST FURNITURE COMPONENT WITH THE AMMONIA FOR THE REQUIRED PERIOD OF TIME, G. OPENING AN ENTRANCE DOOR TO A SECOND AIR LOCK MEANS, SAID LAST MENTIONED ENTRANCE DOOR CONNECTING SAID TREATMENT AREA WITH SAID SECOND AIR LOCK MEANS, H. MOVING SAID FIRST FURNITURE COMPONENT INTO SAID SECOND AIR LOCK MEANS, AND CLOSING THE ENTRANCE DOOR OF SAID SECOND AIR LOCK MEANS WHILE AT THE SAME TIME MOVING SAID SECOND FURNITURE COMPONENT INTO SAID TREATMENT AREA, I. THEN OPENING AN EXIT DOOR OF SAID SECOND AIR LOCK MEANS AND MOVING SAID FIRST FURNITURE COMPONENT FROM SAID SECOND AIR LOCK MEANS TO THE POINT WHEREIN THE FIRST FURNITURE COMPONENT STARTED ITS MOVEMENT TOWARDS THE FIRST AIR LOCK MEANS.
 2. The method of claim 1 wherein there is the further step of: j. exhausting air from the vicinity of the entrance door of the first air lock means and the exit door of the second air lock means to prevent residual ammonia gases in said air lock means from escaping from within the treatment apparatus to the area outside of the treatment apparatus. 